Fkemont swain



(No Model.)

P. SWAIN.

BICYCLE.

Patented Feb 3, 1885.

UiviTnn STaTTs PATENT @rrrcs.

FREMONT SVAIN, OF INDIANAPOLIS, INDIANA.

BICYCLE.

SPECIFICATION forming part of Letters Patent No. 311,687, dated February3, 1885.

Application tiled May 12, 1584. (No model.)

To aZZ whom it may concern;

Be it known that I. FREMONT SWAIN, a citizen of the United States,residing at Indianapolis, in the county of Marion and State otlndiana,have invented a new and useful Improvement in Bicycles, of which the following is a specification.

My improvement relates to that part of a bicycle commonly known as thebackbone, and to that class of bicycles having two driving-wheels andcarrying two riders. and known as the tandem bii-ylc; and the object ofmy improvement is to provide a backbone that can he lengthened orshortened and suit ably adjusted to fit the driving-wheels of any twoordinary bicycles and join them together into a tandem machine. This Iaccomplish by the mechanism illustrated in the accompanying drawings, inwhich Figure l is a side view of my entire invention,showing theposition of the backbone when joining together two wheels having thesame diameter. Fig. 2 is a side view of the backbone when joining twowheels of different diameters. Fig. 3 is a top view of the backbone withboth wheels and thcirconnecting mechanism removed. This view also showsmy method of curving the backbone around the head on the rear wheel whenthe i latter is of the closed-head type, or closed in front, as iscommonly used. Fig. 4 is a vertical longitudinal section of thebackbone. Fig. 5 is a side view of one of the heads or disks in-thejoint for adjusting the seats. The view shows the radially notched orserrated surface to keep the sections from turning upon each other. Fig.6 is a top view of thcjoint, showing the manner in which the notches onthe two contacting or inside faces of the jointheads interlock. Fig. 7is a vertical crosssection through the clamp by which thetelescopicjoint in the backbone is locked.

Similar letters refer to similar parts through out the several views.

A is the front and A the rear wheel. On the front wheehB, is thefork,and b the head. The head I) is provided with upper and lowerbridges, between which the spindle on the front end of the backbone iscentered.

O G are the handlesand 0 the brake, as found on the bicycle of commonform. On the rear 0 G are the same as found on the bicycles of commonform. Both wheels A and A are driving-wheels,propelled by any suitablearrangement of pedals.

So far as above described,the mechanism is old; and the novelty in myinvention consists in the backbone D, by which the two wheels A and Aare connected. and which [will now more fully describe. The heads I) andb are the points at which the backbone is attached. On the front end ofthe backbone, and continuous tl'ierewith, is the vertical spindle g,which is pivoted between the upper and lower bridges in the head I). Acenter screw in the upper bridge affords a means of tightening thespindle, as in the ordinary bicycle. Near the rear end of the backbone,as shown in Figs. 3 and 4, is a second spindle, similar to the one justdescribed. This spindle is centered between the bridges in the head I),and is tightened by means of a center screw, as do scribed for the frontspindle. The saddle J, for the front man.is fastened to the backboneimmediately to the rear of the head I). The saddle for the man behind isfastened to the tail-piece I, which piece is a continuation of thebackbone to a suitable distance beyond the spindle It. The seats maybeot' any known pattern, and i'naybe attached by any known means. Abackbone made of a single piece with the spindles, as described, will beallsufficicnt for wheels of the same diameter; but if the same backboneis used on wheels whose diameters vary. it will be found too long forsmall wheels and too short for large ones, and if used to connect alarge wheel with a small one it will lie at such an angle as to destroythe riding qualities of the attached seat and of the entire machine. Thefirst diiiiculty I overcome by making a telescopicjoint between the twospindles. As shown in the drawings, the middle of the backbone is formedof two concentric tubes, E and F, the outer one of which has alongitudinal slot on its upper side and a clamp, e,(shown incross-section in Fig. 7,) on its end. The slot in the outer tube allowsthe sides to be drawn together by the clamp tight enough to keep thetubes from slipping apart. A nut, f, on a stud fastened to the innertube. and projecting through the slot in the outer one, allows the endof the inwheel the fork B, the head I), and the handles ner tube to besecured to prevent any play that it might have. By means of thetelescopic joint it will be seen that thelengthot' the backbone can bereadily varied to suit the varying distance between the heads band boccasioned by the difference in the diameters of the wheels. Inconnecting a large and a small wheel the sloping position assumed by thebackbone throws the attached seats so much out of place and angle that ameans of adjustment is necessary. This I accomplish by the joints M andM, the joint M being placed to the rear of the front seat, and thejointM in front of the back spindle and as close to it as possible withoutinterfering with the wheel. The details of these joints are best shownin Figs. 5 and 6.

In Fig. 6 the head N is a continuation of the front section of thebackbone, and the head N a continuation of the rear section.

0 and O are thick metal disks or washers, between which the heads N andN are clam pcd by means of the bolt and nut Pp. The inside faces of theheads N and N have long notches running from the rim to the center,which interlock and securely hold the heads from turning each upon theother when brought to gether by the bolt. These two joints M and M allowof the proper adjustment of the saddles independently of the angle whichthe backbone may have.

The practical application of my invention is as follows: The curvedbackbones and small wheels of two bicycles of common form are re movedby loosening the center screws which hold the spindles. The spindles ofmy improved backbone are then adjusted between the bridges in the headsof the two wheels,

and the length of the backbone is properly adjusted by means of thetelescopic joints, after which the proper angle is given to the seats bymeans ofthe twojoints M and M.

In some machines now in use the heads I) and Z2 are open in front,and inothers the front is closed, the only opening being in the rear of thehead to admit the spindle. In the open head the front extension of thebackbone can be passed directly through the opening in the head; but inthe el0sed-head pattern it becomes necessary to have the backbonecurved, as shown in Fig. 3, to pass to one side of the head. In thiscase the neck and attached spindle project forward into the center ofthe curve, and can be readily passed through the opening in the back ofthe head and the spindle placed in position between the bridges.

In adjusting the backbone on wheels having the open head the easiestplan is to draw the telescoping ends entirely apart and again unite themafter passing the rear section through the open head of the rear wheel.

Having thus fully described my invention, what I claim as new, and wishto secure by Letters Patent, is

1. A backbone for tandem bicycles that can be readily lengthened orshortened to connect driving-wheels of any diameter, substantially asdescribed and specified.

2. A backbone for tandem bicycles having atelescopicjointforlengtheningthe backbone. and a suitable means for locking the joint at any desiredpoint, as described and set forth.

3. In a backbone for tandem bicycles, a telescopic joint locked by meansof a clamp at any desired point, as described and set forth.

4. In abackbone for tandem bicycles,ajoint for adjusting the angle ofthe seats, as described and specified.

5. In a backbone fortandem bicycles,ajoint for adjusting the seats,formed of two heads, one attached to and continuous with each adjacentsection of the backbone, the contacting faces of said heads havingnotches which interlock and hold the heads from turning upon each otherwhen brought together by a suitable bolt, substantially as described.

6. In a backbone for tandem bicycles, a

separatejoint for adjusting each of the two seats, as described.

7. In a backbone for transforming bicycles having heads closed in frontinto a tandem machine, the curve B in the backbone opposite therearspindle to pass around the out side of the head, si'ibstantially asdescribed and specified.

8. In a backbone for tandem bicycles, the telescopicjoint for varyingthe length of the backbone, and the joints M and M for adj usting thesaddles, substantially as described and specified.

Signed at Indianapolis,Indiana, in the pres- I00 ence of two witnesses.

FREMONT SWAIN.

Attest:

firms. A. N 100L1 1,

LOUIE HENR

